gearset vs gear mechanism

gearset and gear mechanism both are nouns.

Word	Noun	Adjective	Verb	Adverb
gearset	Yes	No	No	No
gear mechanism	Yes	No	No	No

As nouns, gear mechanism is a hypernym of gearset; that is, gear mechanism is a word with a broader meaning than gearset:

gearset: a set of gears
gear mechanism: a mechanism for transmitting motion for some specific purpose (as the steering gear of a vehicle)

Other hypernyms of gearset include gear.

gearset (noun)	gear mechanism (noun)
a set of gears	a mechanism for transmitting motion for some specific purpose (as the steering gear of a vehicle)